Process for the production of solid particles comprising a material with melting point from −20 to 300° C. at atmospheric pressure, characterized in that a mixture comprising: a1) the material in molten form and a2) the material in solid form is mixed by means of an extruder to give a paste, this is forced through a pelletizing die to give strands, and the strands are comminuted.

A method and apparatus for the pelletization of plastics and/or polymers, in which a melt coming from a melt generator is supplied via a diverter valve having different operating positions to a plurality of pelletizing heads through which the melt is pelletized. The plurality of pelletizing heads have different throughput capacities and are used sequentially for the start-up of the pelletizing process, with the melt first being supplied to a first pelletizing head having a smaller throughput capacity and then the melt volume flow being increased and the diverter valve being switched over such that the melt is diverted by the diverter valve to a second pelletizing head having a larger throughput capacity.

A melt processing plant is provided that includes a melt charger for charging a processing head, in particular a pelletizing head, with melt, in which a diverter valve for discharging the melt during a starting and/or retooling phase is associated to the melt charger upstream of the processing head. A splitter divides the discharged melt into melt portions with the melt channels of the splitter head having at least one step-like cross-sectional enlargement of their inflow portion, a cross-sectional shape different from the outlet cross-section of the discharge channel, and an open orifice region out of the splitter.

The present invention deals with a process for producing pellets from olefin copolymers. The process comprises: (i) melting the olefin copolymer in an extruder; (ii) extruding the molten olefin copolymer through a die plate into a pellet water bath in a pelletiser thereby producing strands of the olefin copolymer; (iii) cutting the strands of the olefin copolymer in the pelletiser into pellets; and (iv) drying the pellets. The pellet water in the pelletiser contains from 0.1 to 5% by weight of a colloidal silica based on the weight of the water.

A process includes contacting a metallic acrylic salt with a polyolefin, forming a polyolefin composition. The process includes extruding the polyolefin composition, and pelletizing the extruded polyolefin composition. A production rate of pellets of the polyolefin composition may be equal to or greater than a production rate of pellets of the polyolefin prior to contact with the metallic acrylic salt without increasing extrusion pressure or motor amperes. The polyolefin composition may have a melt flow rate that is lower than the melt flow rate of the polyolefin prior to contact with the metallic acrylic salt. The metallic acrylic salt may only be contacted with the polyolefin to form the polyolefin composition during a start-up of an extruder and pelletizer.

There is provided a die plate, a resin machine, and a method of heating nozzles of the die plate that can suppress temperature unevenness of the nozzles and increase the temperature rise performance of the nozzles. The die plate includes a nozzle group including a plurality of nozzles through which molten resin passes, and a heating medium guidance part that guides a heating medium for heating a nozzle wall of each nozzle. The heating medium guidance part includes an inlet that receives the heating medium, an outlet that discharges the heating medium from a heating medium channel, and a guidance wall that defines a heating channel that causes the inlet and the outlet to be in communication with each other together with an outer peripheral surface of the nozzle wall of each of the plurality of nozzles.

The present invention relates to an extruded expanded thermoplastic polyurethane elastomer bead and a preparation method therefor. The bead consists of components of the following parts by weight: 100 parts by weight of a thermoplastic polyurethane elastomer, 0.01-0.5 parts of a foaming nucleating agent, and 0.01-0.2 parts by weight of an antioxidant. The preparation method comprises: mixing materials, then putting the mixture into an extruder for granulation to produce a particle raw material suitable for foaming, finally, putting the particle into a foam extruder, and die foaming then underwater pelletizing, thus obtaining a product bead. The present invention utilizes an extrusion method to prepare expanded thermoplastic polyurethane beads. Control of the working conditions of the foaming process could lead to acquiring an expanded=bead of a controllable density, the cell density evenly distribute. The overall production process is easy to operate. Without any special limit or requirement placed on the equipment, this method is suitable for industrial continuous production.

The invention relates to a method for producing a plastic granulate (16), in which a process fluid (12) is contained in a process chamber (10) where an underwater granulation takes place and the process fluid in the process chamber has a temperature greater than 120° C. A process pressure of at least 2.0 bar is obtained in the process chamber, at which a granulation of the plastic strands (14) into plastic granulate occurs. From the process chamber, a mixture (18) of process fluid and plastic granulate is diverted into a first cooling zone (25) during cooling of the plastic granulate, while maintaining the process pressure. In a first separating device (22), the plastic granulate is separated from the process fluid under process pressure. In the process chamber, the process fluid has a temperature in the range from 120° C. to 160° C., and the process pressure obtained there is greater than the pressure of the vapour pressure curve of the process fluid. After separation from the process fluid in the first separating device, the plastic granulate is fed continuously in a line to a dealdehydization container (46).

An apparatus and process to maintain control of the temperature of low-melting compounds, high melt flow polymers, and thermally sensitive materials for the pelletization of such materials. The addition of a cooling extruder, and a second melt cooler if desired, in advance of the die plate provides for regulation of the thermal, shear, and rheological characteristics of narrow melting-range materials and polymeric mixtures, formulations, dispersions or solutions. The apparatus and process can then be highly regulated to produce consistent, uniform pellets of low moisture content for these otherwise difficult materials to pelletize.

The present invention relates to expanded thermoplastic polyurethane beads, a preparation method for same, and an application thereof. The expanded thermoplastic polyurethane beads consists of components of the following parts by weight: 100 parts of a thermoplastic polyurethane, 1-10 parts of a cell size stabilizer, and 1-35 parts of a melt viscosity modifier. The preparation method for the expanded thermoplastic polyurethane beads is also disclosed. The bead is produced by employing a volatile blowing agent to immerse the thermoplastic polyurethane, comprising the pore size stabilizer and the melt viscosity modifier, in an aqueous suspension, and is then followed by the foaming process. Utilization of the expanded thermoplastic polyurethane beads of the present invention allows for preparation of a foam product. The expanded thermoplastic polyurethane beads prepared per the present invention has uniform cell sizes and a high product yield. At the same time, the expanded thermoplastic polyurethane bead provides a great sintering performance even at a relatively low vapor pressure, a molded foam product has a small deformation, a low dimensional shrinkage ratio relative to a mold, great dimensional stability, and an aesthetically appealing appearance.